US Patent 7632420 Laser removal of layer or coating from a substrate

A method for treating a substrate having a layer or coating of material thereon (such as for example a metal conductor coated with an insulating ‘enamel’) comprises the steps of directing a pulsed beam of laser radiation at the substrate to cause an interaction or adjacent the interface between the layer or coating and the substrate, leading to local separation of the layer or coating. The removal is effected by creating an interaction effect at the interface between the substrate and the layer or coating to create an effect similar to a shockwave which causes local separation of the layer or coating at the interface.